xref: /openbsd-src/usr.bin/tmux/tty.c (revision 46035553bfdd96e63c94e32da0210227ec2e3cf1)
1 /* $OpenBSD: tty.c,v 1.387 2020/12/03 07:12:12 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 
22 #include <netinet/in.h>
23 
24 #include <curses.h>
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <resolv.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <termios.h>
31 #include <unistd.h>
32 
33 #include "tmux.h"
34 
35 static int	tty_log_fd = -1;
36 
37 static int	tty_client_ready(struct client *);
38 
39 static void	tty_set_italics(struct tty *);
40 static int	tty_try_colour(struct tty *, int, const char *);
41 static void	tty_force_cursor_colour(struct tty *, const char *);
42 static void	tty_cursor_pane(struct tty *, const struct tty_ctx *, u_int,
43 		    u_int);
44 static void	tty_cursor_pane_unless_wrap(struct tty *,
45 		    const struct tty_ctx *, u_int, u_int);
46 static void	tty_invalidate(struct tty *);
47 static void	tty_colours(struct tty *, const struct grid_cell *);
48 static void	tty_check_fg(struct tty *, int *, struct grid_cell *);
49 static void	tty_check_bg(struct tty *, int *, struct grid_cell *);
50 static void	tty_check_us(struct tty *, int *, struct grid_cell *);
51 static void	tty_colours_fg(struct tty *, const struct grid_cell *);
52 static void	tty_colours_bg(struct tty *, const struct grid_cell *);
53 static void	tty_colours_us(struct tty *, const struct grid_cell *);
54 
55 static void	tty_region_pane(struct tty *, const struct tty_ctx *, u_int,
56 		    u_int);
57 static void	tty_region(struct tty *, u_int, u_int);
58 static void	tty_margin_pane(struct tty *, const struct tty_ctx *);
59 static void	tty_margin(struct tty *, u_int, u_int);
60 static int	tty_large_region(struct tty *, const struct tty_ctx *);
61 static int	tty_fake_bce(const struct tty *, const struct grid_cell *,
62 		    u_int);
63 static void	tty_redraw_region(struct tty *, const struct tty_ctx *);
64 static void	tty_emulate_repeat(struct tty *, enum tty_code_code,
65 		    enum tty_code_code, u_int);
66 static void	tty_repeat_space(struct tty *, u_int);
67 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
68 static void	tty_default_attributes(struct tty *, const struct grid_cell *,
69 		    int *, u_int);
70 
71 #define tty_use_margin(tty) \
72 	(tty->term->flags & TERM_DECSLRM)
73 #define tty_full_width(tty, ctx) \
74 	((ctx)->xoff == 0 && (ctx)->sx >= (tty)->sx)
75 
76 #define TTY_BLOCK_INTERVAL (100000 /* 100 milliseconds */)
77 #define TTY_BLOCK_START(tty) (1 + ((tty)->sx * (tty)->sy) * 8)
78 #define TTY_BLOCK_STOP(tty) (1 + ((tty)->sx * (tty)->sy) / 8)
79 
80 void
81 tty_create_log(void)
82 {
83 	char	name[64];
84 
85 	xsnprintf(name, sizeof name, "tmux-out-%ld.log", (long)getpid());
86 
87 	tty_log_fd = open(name, O_WRONLY|O_CREAT|O_TRUNC, 0644);
88 	if (tty_log_fd != -1 && fcntl(tty_log_fd, F_SETFD, FD_CLOEXEC) == -1)
89 		fatal("fcntl failed");
90 }
91 
92 int
93 tty_init(struct tty *tty, struct client *c)
94 {
95 	if (!isatty(c->fd))
96 		return (-1);
97 
98 	memset(tty, 0, sizeof *tty);
99 	tty->client = c;
100 
101 	tty->cstyle = 0;
102 	tty->ccolour = xstrdup("");
103 
104 	if (tcgetattr(c->fd, &tty->tio) != 0)
105 		return (-1);
106 	return (0);
107 }
108 
109 void
110 tty_resize(struct tty *tty)
111 {
112 	struct client	*c = tty->client;
113 	struct winsize	 ws;
114 	u_int		 sx, sy, xpixel, ypixel;
115 
116 	if (ioctl(c->fd, TIOCGWINSZ, &ws) != -1) {
117 		sx = ws.ws_col;
118 		if (sx == 0) {
119 			sx = 80;
120 			xpixel = 0;
121 		} else
122 			xpixel = ws.ws_xpixel / sx;
123 		sy = ws.ws_row;
124 		if (sy == 0) {
125 			sy = 24;
126 			ypixel = 0;
127 		} else
128 			ypixel = ws.ws_ypixel / sy;
129 	} else {
130 		sx = 80;
131 		sy = 24;
132 		xpixel = 0;
133 		ypixel = 0;
134 	}
135 	log_debug("%s: %s now %ux%u (%ux%u)", __func__, c->name, sx, sy,
136 	    xpixel, ypixel);
137 	tty_set_size(tty, sx, sy, xpixel, ypixel);
138 	tty_invalidate(tty);
139 }
140 
141 void
142 tty_set_size(struct tty *tty, u_int sx, u_int sy, u_int xpixel, u_int ypixel)
143 {
144 	tty->sx = sx;
145 	tty->sy = sy;
146 	tty->xpixel = xpixel;
147 	tty->ypixel = ypixel;
148 }
149 
150 static void
151 tty_read_callback(__unused int fd, __unused short events, void *data)
152 {
153 	struct tty	*tty = data;
154 	struct client	*c = tty->client;
155 	const char	*name = c->name;
156 	size_t		 size = EVBUFFER_LENGTH(tty->in);
157 	int		 nread;
158 
159 	nread = evbuffer_read(tty->in, c->fd, -1);
160 	if (nread == 0 || nread == -1) {
161 		if (nread == 0)
162 			log_debug("%s: read closed", name);
163 		else
164 			log_debug("%s: read error: %s", name, strerror(errno));
165 		event_del(&tty->event_in);
166 		server_client_lost(tty->client);
167 		return;
168 	}
169 	log_debug("%s: read %d bytes (already %zu)", name, nread, size);
170 
171 	while (tty_keys_next(tty))
172 		;
173 }
174 
175 static void
176 tty_timer_callback(__unused int fd, __unused short events, void *data)
177 {
178 	struct tty	*tty = data;
179 	struct client	*c = tty->client;
180 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
181 
182 	log_debug("%s: %zu discarded", c->name, tty->discarded);
183 
184 	c->flags |= CLIENT_ALLREDRAWFLAGS;
185 	c->discarded += tty->discarded;
186 
187 	if (tty->discarded < TTY_BLOCK_STOP(tty)) {
188 		tty->flags &= ~TTY_BLOCK;
189 		tty_invalidate(tty);
190 		return;
191 	}
192 	tty->discarded = 0;
193 	evtimer_add(&tty->timer, &tv);
194 }
195 
196 static int
197 tty_block_maybe(struct tty *tty)
198 {
199 	struct client	*c = tty->client;
200 	size_t		 size = EVBUFFER_LENGTH(tty->out);
201 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
202 
203 	if (size < TTY_BLOCK_START(tty))
204 		return (0);
205 
206 	if (tty->flags & TTY_BLOCK)
207 		return (1);
208 	tty->flags |= TTY_BLOCK;
209 
210 	log_debug("%s: can't keep up, %zu discarded", c->name, size);
211 
212 	evbuffer_drain(tty->out, size);
213 	c->discarded += size;
214 
215 	tty->discarded = 0;
216 	evtimer_add(&tty->timer, &tv);
217 	return (1);
218 }
219 
220 static void
221 tty_write_callback(__unused int fd, __unused short events, void *data)
222 {
223 	struct tty	*tty = data;
224 	struct client	*c = tty->client;
225 	size_t		 size = EVBUFFER_LENGTH(tty->out);
226 	int		 nwrite;
227 
228 	nwrite = evbuffer_write(tty->out, c->fd);
229 	if (nwrite == -1)
230 		return;
231 	log_debug("%s: wrote %d bytes (of %zu)", c->name, nwrite, size);
232 
233 	if (c->redraw > 0) {
234 		if ((size_t)nwrite >= c->redraw)
235 			c->redraw = 0;
236 		else
237 			c->redraw -= nwrite;
238 		log_debug("%s: waiting for redraw, %zu bytes left", c->name,
239 		    c->redraw);
240 	} else if (tty_block_maybe(tty))
241 		return;
242 
243 	if (EVBUFFER_LENGTH(tty->out) != 0)
244 		event_add(&tty->event_out, NULL);
245 }
246 
247 int
248 tty_open(struct tty *tty, char **cause)
249 {
250 	struct client	*c = tty->client;
251 
252 	tty->term = tty_term_create(tty, c->term_name, &c->term_features,
253 	    c->fd, cause);
254 	if (tty->term == NULL) {
255 		tty_close(tty);
256 		return (-1);
257 	}
258 	tty->flags |= TTY_OPENED;
259 
260 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE|TTY_BLOCK|TTY_TIMER);
261 
262 	event_set(&tty->event_in, c->fd, EV_PERSIST|EV_READ,
263 	    tty_read_callback, tty);
264 	tty->in = evbuffer_new();
265 	if (tty->in == NULL)
266 		fatal("out of memory");
267 
268 	event_set(&tty->event_out, c->fd, EV_WRITE, tty_write_callback, tty);
269 	tty->out = evbuffer_new();
270 	if (tty->out == NULL)
271 		fatal("out of memory");
272 
273 	evtimer_set(&tty->timer, tty_timer_callback, tty);
274 
275 	tty_start_tty(tty);
276 
277 	tty_keys_build(tty);
278 
279 	return (0);
280 }
281 
282 static void
283 tty_start_timer_callback(__unused int fd, __unused short events, void *data)
284 {
285 	struct tty	*tty = data;
286 	struct client	*c = tty->client;
287 
288 	log_debug("%s: start timer fired", c->name);
289 	if ((tty->flags & (TTY_HAVEDA|TTY_HAVEXDA)) == 0)
290 		tty_update_features(tty);
291 	tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
292 }
293 
294 void
295 tty_start_tty(struct tty *tty)
296 {
297 	struct client	*c = tty->client;
298 	struct termios	 tio;
299 	struct timeval	 tv = { .tv_sec = 1 };
300 
301 	setblocking(c->fd, 0);
302 	event_add(&tty->event_in, NULL);
303 
304 	memcpy(&tio, &tty->tio, sizeof tio);
305 	tio.c_iflag &= ~(IXON|IXOFF|ICRNL|INLCR|IGNCR|IMAXBEL|ISTRIP);
306 	tio.c_iflag |= IGNBRK;
307 	tio.c_oflag &= ~(OPOST|ONLCR|OCRNL|ONLRET);
308 	tio.c_lflag &= ~(IEXTEN|ICANON|ECHO|ECHOE|ECHONL|ECHOCTL|ECHOPRT|
309 	    ECHOKE|ISIG);
310 	tio.c_cc[VMIN] = 1;
311 	tio.c_cc[VTIME] = 0;
312 	if (tcsetattr(c->fd, TCSANOW, &tio) == 0)
313 		tcflush(c->fd, TCIOFLUSH);
314 
315 	tty_putcode(tty, TTYC_SMCUP);
316 
317 	tty_putcode(tty, TTYC_SMKX);
318 	tty_putcode(tty, TTYC_CLEAR);
319 
320 	if (tty_acs_needed(tty)) {
321 		log_debug("%s: using capabilities for ACS", c->name);
322 		tty_putcode(tty, TTYC_ENACS);
323 	} else
324 		log_debug("%s: using UTF-8 for ACS", c->name);
325 
326 	tty_putcode(tty, TTYC_CNORM);
327 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
328 		tty_puts(tty, "\033[?1000l\033[?1002l\033[?1003l");
329 		tty_puts(tty, "\033[?1006l\033[?1005l");
330 	}
331 
332 	evtimer_set(&tty->start_timer, tty_start_timer_callback, tty);
333 	evtimer_add(&tty->start_timer, &tv);
334 
335 	tty->flags |= TTY_STARTED;
336 	tty_invalidate(tty);
337 
338 	if (*tty->ccolour != '\0')
339 		tty_force_cursor_colour(tty, "");
340 
341 	tty->mouse_drag_flag = 0;
342 	tty->mouse_drag_update = NULL;
343 	tty->mouse_drag_release = NULL;
344 }
345 
346 void
347 tty_send_requests(struct tty *tty)
348 {
349 	if (~tty->flags & TTY_STARTED)
350 		return;
351 
352 	if (tty->term->flags & TERM_VT100LIKE) {
353 		if (~tty->flags & TTY_HAVEDA)
354 			tty_puts(tty, "\033[>c");
355 		if (~tty->flags & TTY_HAVEXDA)
356 			tty_puts(tty, "\033[>q");
357 	} else
358 		tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
359 }
360 
361 void
362 tty_stop_tty(struct tty *tty)
363 {
364 	struct client	*c = tty->client;
365 	struct winsize	 ws;
366 
367 	if (!(tty->flags & TTY_STARTED))
368 		return;
369 	tty->flags &= ~TTY_STARTED;
370 
371 	evtimer_del(&tty->start_timer);
372 
373 	event_del(&tty->timer);
374 	tty->flags &= ~TTY_BLOCK;
375 
376 	event_del(&tty->event_in);
377 	event_del(&tty->event_out);
378 
379 	/*
380 	 * Be flexible about error handling and try not kill the server just
381 	 * because the fd is invalid. Things like ssh -t can easily leave us
382 	 * with a dead tty.
383 	 */
384 	if (ioctl(c->fd, TIOCGWINSZ, &ws) == -1)
385 		return;
386 	if (tcsetattr(c->fd, TCSANOW, &tty->tio) == -1)
387 		return;
388 
389 	tty_raw(tty, tty_term_string2(tty->term, TTYC_CSR, 0, ws.ws_row - 1));
390 	if (tty_acs_needed(tty))
391 		tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
392 	tty_raw(tty, tty_term_string(tty->term, TTYC_SGR0));
393 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMKX));
394 	tty_raw(tty, tty_term_string(tty->term, TTYC_CLEAR));
395 	if (tty_term_has(tty->term, TTYC_SS) && tty->cstyle != 0) {
396 		if (tty_term_has(tty->term, TTYC_SE))
397 			tty_raw(tty, tty_term_string(tty->term, TTYC_SE));
398 		else
399 			tty_raw(tty, tty_term_string1(tty->term, TTYC_SS, 0));
400 	}
401 	if (tty->mode & MODE_BRACKETPASTE)
402 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
403 	if (*tty->ccolour != '\0')
404 		tty_raw(tty, tty_term_string(tty->term, TTYC_CR));
405 
406 	tty_raw(tty, tty_term_string(tty->term, TTYC_CNORM));
407 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
408 		tty_raw(tty, "\033[?1000l\033[?1002l\033[?1003l");
409 		tty_raw(tty, "\033[?1006l\033[?1005l");
410 	}
411 
412 	if (tty->term->flags & TERM_VT100LIKE)
413 		tty_raw(tty, "\033[?7727l");
414 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSFCS));
415 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSEKS));
416 
417 	if (tty_use_margin(tty))
418 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSMG));
419 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMCUP));
420 
421 	setblocking(c->fd, 1);
422 }
423 
424 void
425 tty_close(struct tty *tty)
426 {
427 	if (event_initialized(&tty->key_timer))
428 		evtimer_del(&tty->key_timer);
429 	tty_stop_tty(tty);
430 
431 	if (tty->flags & TTY_OPENED) {
432 		evbuffer_free(tty->in);
433 		event_del(&tty->event_in);
434 		evbuffer_free(tty->out);
435 		event_del(&tty->event_out);
436 
437 		tty_term_free(tty->term);
438 		tty_keys_free(tty);
439 
440 		tty->flags &= ~TTY_OPENED;
441 	}
442 }
443 
444 void
445 tty_free(struct tty *tty)
446 {
447 	tty_close(tty);
448 	free(tty->ccolour);
449 }
450 
451 void
452 tty_update_features(struct tty *tty)
453 {
454 	struct client	*c = tty->client;
455 
456 	if (tty_apply_features(tty->term, c->term_features))
457 		tty_term_apply_overrides(tty->term);
458 
459 	if (tty_use_margin(tty))
460 		tty_putcode(tty, TTYC_ENMG);
461 	if (options_get_number(global_options, "extended-keys"))
462 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENEKS));
463 	if (options_get_number(global_options, "focus-events"))
464 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENFCS));
465 	if (tty->term->flags & TERM_VT100LIKE)
466 		tty_puts(tty, "\033[?7727h");
467 }
468 
469 void
470 tty_raw(struct tty *tty, const char *s)
471 {
472 	struct client	*c = tty->client;
473 	ssize_t		 n, slen;
474 	u_int		 i;
475 
476 	slen = strlen(s);
477 	for (i = 0; i < 5; i++) {
478 		n = write(c->fd, s, slen);
479 		if (n >= 0) {
480 			s += n;
481 			slen -= n;
482 			if (slen == 0)
483 				break;
484 		} else if (n == -1 && errno != EAGAIN)
485 			break;
486 		usleep(100);
487 	}
488 }
489 
490 void
491 tty_putcode(struct tty *tty, enum tty_code_code code)
492 {
493 	tty_puts(tty, tty_term_string(tty->term, code));
494 }
495 
496 void
497 tty_putcode1(struct tty *tty, enum tty_code_code code, int a)
498 {
499 	if (a < 0)
500 		return;
501 	tty_puts(tty, tty_term_string1(tty->term, code, a));
502 }
503 
504 void
505 tty_putcode2(struct tty *tty, enum tty_code_code code, int a, int b)
506 {
507 	if (a < 0 || b < 0)
508 		return;
509 	tty_puts(tty, tty_term_string2(tty->term, code, a, b));
510 }
511 
512 void
513 tty_putcode3(struct tty *tty, enum tty_code_code code, int a, int b, int c)
514 {
515 	if (a < 0 || b < 0 || c < 0)
516 		return;
517 	tty_puts(tty, tty_term_string3(tty->term, code, a, b, c));
518 }
519 
520 void
521 tty_putcode_ptr1(struct tty *tty, enum tty_code_code code, const void *a)
522 {
523 	if (a != NULL)
524 		tty_puts(tty, tty_term_ptr1(tty->term, code, a));
525 }
526 
527 void
528 tty_putcode_ptr2(struct tty *tty, enum tty_code_code code, const void *a,
529     const void *b)
530 {
531 	if (a != NULL && b != NULL)
532 		tty_puts(tty, tty_term_ptr2(tty->term, code, a, b));
533 }
534 
535 static void
536 tty_add(struct tty *tty, const char *buf, size_t len)
537 {
538 	struct client	*c = tty->client;
539 
540 	if (tty->flags & TTY_BLOCK) {
541 		tty->discarded += len;
542 		return;
543 	}
544 
545 	evbuffer_add(tty->out, buf, len);
546 	log_debug("%s: %.*s", c->name, (int)len, buf);
547 	c->written += len;
548 
549 	if (tty_log_fd != -1)
550 		write(tty_log_fd, buf, len);
551 	if (tty->flags & TTY_STARTED)
552 		event_add(&tty->event_out, NULL);
553 }
554 
555 void
556 tty_puts(struct tty *tty, const char *s)
557 {
558 	if (*s != '\0')
559 		tty_add(tty, s, strlen(s));
560 }
561 
562 void
563 tty_putc(struct tty *tty, u_char ch)
564 {
565 	const char	*acs;
566 
567 	if ((tty->term->flags & TERM_NOAM) &&
568 	    ch >= 0x20 && ch != 0x7f &&
569 	    tty->cy == tty->sy - 1 &&
570 	    tty->cx + 1 >= tty->sx)
571 		return;
572 
573 	if (tty->cell.attr & GRID_ATTR_CHARSET) {
574 		acs = tty_acs_get(tty, ch);
575 		if (acs != NULL)
576 			tty_add(tty, acs, strlen(acs));
577 		else
578 			tty_add(tty, &ch, 1);
579 	} else
580 		tty_add(tty, &ch, 1);
581 
582 	if (ch >= 0x20 && ch != 0x7f) {
583 		if (tty->cx >= tty->sx) {
584 			tty->cx = 1;
585 			if (tty->cy != tty->rlower)
586 				tty->cy++;
587 
588 			/*
589 			 * On !am terminals, force the cursor position to where
590 			 * we think it should be after a line wrap - this means
591 			 * it works on sensible terminals as well.
592 			 */
593 			if (tty->term->flags & TERM_NOAM)
594 				tty_putcode2(tty, TTYC_CUP, tty->cy, tty->cx);
595 		} else
596 			tty->cx++;
597 	}
598 }
599 
600 void
601 tty_putn(struct tty *tty, const void *buf, size_t len, u_int width)
602 {
603 	if ((tty->term->flags & TERM_NOAM) &&
604 	    tty->cy == tty->sy - 1 &&
605 	    tty->cx + len >= tty->sx)
606 		len = tty->sx - tty->cx - 1;
607 
608 	tty_add(tty, buf, len);
609 	if (tty->cx + width > tty->sx) {
610 		tty->cx = (tty->cx + width) - tty->sx;
611 		if (tty->cx <= tty->sx)
612 			tty->cy++;
613 		else
614 			tty->cx = tty->cy = UINT_MAX;
615 	} else
616 		tty->cx += width;
617 }
618 
619 static void
620 tty_set_italics(struct tty *tty)
621 {
622 	const char	*s;
623 
624 	if (tty_term_has(tty->term, TTYC_SITM)) {
625 		s = options_get_string(global_options, "default-terminal");
626 		if (strcmp(s, "screen") != 0 && strncmp(s, "screen-", 7) != 0) {
627 			tty_putcode(tty, TTYC_SITM);
628 			return;
629 		}
630 	}
631 	tty_putcode(tty, TTYC_SMSO);
632 }
633 
634 void
635 tty_set_title(struct tty *tty, const char *title)
636 {
637 	if (!tty_term_has(tty->term, TTYC_TSL) ||
638 	    !tty_term_has(tty->term, TTYC_FSL))
639 		return;
640 
641 	tty_putcode(tty, TTYC_TSL);
642 	tty_puts(tty, title);
643 	tty_putcode(tty, TTYC_FSL);
644 }
645 
646 static void
647 tty_force_cursor_colour(struct tty *tty, const char *ccolour)
648 {
649 	if (*ccolour == '\0')
650 		tty_putcode(tty, TTYC_CR);
651 	else
652 		tty_putcode_ptr1(tty, TTYC_CS, ccolour);
653 	free(tty->ccolour);
654 	tty->ccolour = xstrdup(ccolour);
655 }
656 
657 void
658 tty_update_mode(struct tty *tty, int mode, struct screen *s)
659 {
660 	struct client	*c = tty->client;
661 	int		 changed;
662 
663 	if (s != NULL && strcmp(s->ccolour, tty->ccolour) != 0)
664 		tty_force_cursor_colour(tty, s->ccolour);
665 
666 	if (tty->flags & TTY_NOCURSOR)
667 		mode &= ~MODE_CURSOR;
668 
669 	changed = mode ^ tty->mode;
670 	if (changed != 0)
671 		log_debug("%s: update mode %x to %x", c->name, tty->mode, mode);
672 
673 	if (changed & MODE_BLINKING) {
674 		if (tty_term_has(tty->term, TTYC_CVVIS))
675 			tty_putcode(tty, TTYC_CVVIS);
676 		else
677 			tty_putcode(tty, TTYC_CNORM);
678 		changed |= MODE_CURSOR;
679 	}
680 	if (changed & MODE_CURSOR) {
681 		if (mode & MODE_CURSOR)
682 			tty_putcode(tty, TTYC_CNORM);
683 		else
684 			tty_putcode(tty, TTYC_CIVIS);
685 	}
686 	if (s != NULL && tty->cstyle != s->cstyle) {
687 		if (tty_term_has(tty->term, TTYC_SS)) {
688 			if (s->cstyle == 0 && tty_term_has(tty->term, TTYC_SE))
689 				tty_putcode(tty, TTYC_SE);
690 			else
691 				tty_putcode1(tty, TTYC_SS, s->cstyle);
692 		}
693 		tty->cstyle = s->cstyle;
694 	}
695 	if ((changed & ALL_MOUSE_MODES) &&
696 	    tty_term_has(tty->term, TTYC_KMOUS)) {
697 		/*
698 		 * If the mouse modes have changed, clear any that are set and
699 		 * apply again. There are differences in how terminals track
700 		 * the various bits.
701 		 */
702 		if (tty->mode & MODE_MOUSE_SGR)
703 			tty_puts(tty, "\033[?1006l");
704 		if (tty->mode & MODE_MOUSE_STANDARD)
705 			tty_puts(tty, "\033[?1000l");
706 		if (tty->mode & MODE_MOUSE_BUTTON)
707 			tty_puts(tty, "\033[?1002l");
708 		if (tty->mode & MODE_MOUSE_ALL)
709 			tty_puts(tty, "\033[?1003l");
710 		if (mode & ALL_MOUSE_MODES)
711 			tty_puts(tty, "\033[?1006h");
712 		if (mode & MODE_MOUSE_STANDARD)
713 			tty_puts(tty, "\033[?1000h");
714 		if (mode & MODE_MOUSE_BUTTON)
715 			tty_puts(tty, "\033[?1002h");
716 		if (mode & MODE_MOUSE_ALL)
717 			tty_puts(tty, "\033[?1003h");
718 	}
719 	if (changed & MODE_BRACKETPASTE) {
720 		if (mode & MODE_BRACKETPASTE)
721 			tty_putcode(tty, TTYC_ENBP);
722 		else
723 			tty_putcode(tty, TTYC_DSBP);
724 	}
725 	tty->mode = mode;
726 }
727 
728 static void
729 tty_emulate_repeat(struct tty *tty, enum tty_code_code code,
730     enum tty_code_code code1, u_int n)
731 {
732 	if (tty_term_has(tty->term, code))
733 		tty_putcode1(tty, code, n);
734 	else {
735 		while (n-- > 0)
736 			tty_putcode(tty, code1);
737 	}
738 }
739 
740 static void
741 tty_repeat_space(struct tty *tty, u_int n)
742 {
743 	static char s[500];
744 
745 	if (*s != ' ')
746 		memset(s, ' ', sizeof s);
747 
748 	while (n > sizeof s) {
749 		tty_putn(tty, s, sizeof s, sizeof s);
750 		n -= sizeof s;
751 	}
752 	if (n != 0)
753 		tty_putn(tty, s, n, n);
754 }
755 
756 /* Is this window bigger than the terminal? */
757 int
758 tty_window_bigger(struct tty *tty)
759 {
760 	struct client	*c = tty->client;
761 	struct window	*w = c->session->curw->window;
762 
763 	return (tty->sx < w->sx || tty->sy - status_line_size(c) < w->sy);
764 }
765 
766 /* What offset should this window be drawn at? */
767 int
768 tty_window_offset(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
769 {
770 	*ox = tty->oox;
771 	*oy = tty->ooy;
772 	*sx = tty->osx;
773 	*sy = tty->osy;
774 
775 	return (tty->oflag);
776 }
777 
778 /* What offset should this window be drawn at? */
779 static int
780 tty_window_offset1(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
781 {
782 	struct client		*c = tty->client;
783 	struct window		*w = c->session->curw->window;
784 	struct window_pane	*wp = server_client_get_pane(c);
785 	u_int			 cx, cy, lines;
786 
787 	lines = status_line_size(c);
788 
789 	if (tty->sx >= w->sx && tty->sy - lines >= w->sy) {
790 		*ox = 0;
791 		*oy = 0;
792 		*sx = w->sx;
793 		*sy = w->sy;
794 
795 		c->pan_window = NULL;
796 		return (0);
797 	}
798 
799 	*sx = tty->sx;
800 	*sy = tty->sy - lines;
801 
802 	if (c->pan_window == w) {
803 		if (*sx >= w->sx)
804 			c->pan_ox = 0;
805 		else if (c->pan_ox + *sx > w->sx)
806 			c->pan_ox = w->sx - *sx;
807 		*ox = c->pan_ox;
808 		if (*sy >= w->sy)
809 			c->pan_oy = 0;
810 		else if (c->pan_oy + *sy > w->sy)
811 			c->pan_oy = w->sy - *sy;
812 		*oy = c->pan_oy;
813 		return (1);
814 	}
815 
816 	if (~wp->screen->mode & MODE_CURSOR) {
817 		*ox = 0;
818 		*oy = 0;
819 	} else {
820 		cx = wp->xoff + wp->screen->cx;
821 		cy = wp->yoff + wp->screen->cy;
822 
823 		if (cx < *sx)
824 			*ox = 0;
825 		else if (cx > w->sx - *sx)
826 			*ox = w->sx - *sx;
827 		else
828 			*ox = cx - *sx / 2;
829 
830 		if (cy < *sy)
831 			*oy = 0;
832 		else if (cy > w->sy - *sy)
833 			*oy = w->sy - *sy;
834 		else
835 			*oy = cy - *sy / 2;
836 	}
837 
838 	c->pan_window = NULL;
839 	return (1);
840 }
841 
842 /* Update stored offsets for a window and redraw if necessary. */
843 void
844 tty_update_window_offset(struct window *w)
845 {
846 	struct client	*c;
847 
848 	TAILQ_FOREACH(c, &clients, entry) {
849 		if (c->session != NULL && c->session->curw->window == w)
850 			tty_update_client_offset(c);
851 	}
852 }
853 
854 /* Update stored offsets for a client and redraw if necessary. */
855 void
856 tty_update_client_offset(struct client *c)
857 {
858 	u_int	ox, oy, sx, sy;
859 
860 	if (~c->flags & CLIENT_TERMINAL)
861 		return;
862 
863 	c->tty.oflag = tty_window_offset1(&c->tty, &ox, &oy, &sx, &sy);
864 	if (ox == c->tty.oox &&
865 	    oy == c->tty.ooy &&
866 	    sx == c->tty.osx &&
867 	    sy == c->tty.osy)
868 		return;
869 
870 	log_debug ("%s: %s offset has changed (%u,%u %ux%u -> %u,%u %ux%u)",
871 	    __func__, c->name, c->tty.oox, c->tty.ooy, c->tty.osx, c->tty.osy,
872 	    ox, oy, sx, sy);
873 
874 	c->tty.oox = ox;
875 	c->tty.ooy = oy;
876 	c->tty.osx = sx;
877 	c->tty.osy = sy;
878 
879 	c->flags |= (CLIENT_REDRAWWINDOW|CLIENT_REDRAWSTATUS);
880 }
881 
882 /* Get a palette entry. */
883 static int
884 tty_get_palette(int *palette, int c)
885 {
886 	int	new;
887 
888 	if (palette == NULL)
889 		return (-1);
890 
891 	new = -1;
892 	if (c < 8)
893 		new = palette[c];
894 	else if (c >= 90 && c <= 97)
895 		new = palette[8 + c - 90];
896 	else if (c & COLOUR_FLAG_256)
897 		new = palette[c & ~COLOUR_FLAG_256];
898 	if (new == 0)
899 		return (-1);
900 	return (new);
901 }
902 
903 /*
904  * Is the region large enough to be worth redrawing once later rather than
905  * probably several times now? Currently yes if it is more than 50% of the
906  * pane.
907  */
908 static int
909 tty_large_region(__unused struct tty *tty, const struct tty_ctx *ctx)
910 {
911 	return (ctx->orlower - ctx->orupper >= ctx->sy / 2);
912 }
913 
914 /*
915  * Return if BCE is needed but the terminal doesn't have it - it'll need to be
916  * emulated.
917  */
918 static int
919 tty_fake_bce(const struct tty *tty, const struct grid_cell *gc, u_int bg)
920 {
921 	if (tty_term_flag(tty->term, TTYC_BCE))
922 		return (0);
923 	if (!COLOUR_DEFAULT(bg) || !COLOUR_DEFAULT(gc->bg))
924 		return (1);
925 	return (0);
926 }
927 
928 /*
929  * Redraw scroll region using data from screen (already updated). Used when
930  * CSR not supported, or window is a pane that doesn't take up the full
931  * width of the terminal.
932  */
933 static void
934 tty_redraw_region(struct tty *tty, const struct tty_ctx *ctx)
935 {
936 	struct client		*c = tty->client;
937 	u_int			 i;
938 
939 	/*
940 	 * If region is large, schedule a redraw. In most cases this is likely
941 	 * to be followed by some more scrolling.
942 	 */
943 	if (tty_large_region(tty, ctx)) {
944 		log_debug("%s: %s large redraw", __func__, c->name);
945 		ctx->redraw_cb(ctx);
946 		return;
947 	}
948 
949 	if (ctx->ocy < ctx->orupper || ctx->ocy > ctx->orlower) {
950 		for (i = ctx->ocy; i < ctx->sy; i++)
951 			tty_draw_pane(tty, ctx, i);
952 	} else {
953 		for (i = ctx->orupper; i <= ctx->orlower; i++)
954 			tty_draw_pane(tty, ctx, i);
955 	}
956 }
957 
958 /* Is this position visible in the pane? */
959 static int
960 tty_is_visible(__unused struct tty *tty, const struct tty_ctx *ctx, u_int px,
961     u_int py, u_int nx, u_int ny)
962 {
963 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
964 
965 	if (!ctx->bigger)
966 		return (1);
967 
968 	if (xoff + nx <= ctx->wox || xoff >= ctx->wox + ctx->wsx ||
969 	    yoff + ny <= ctx->woy || yoff >= ctx->woy + ctx->wsy)
970 		return (0);
971 	return (1);
972 }
973 
974 /* Clamp line position to visible part of pane. */
975 static int
976 tty_clamp_line(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
977     u_int nx, u_int *i, u_int *x, u_int *rx, u_int *ry)
978 {
979 	u_int	xoff = ctx->rxoff + px;
980 
981 	if (!tty_is_visible(tty, ctx, px, py, nx, 1))
982 		return (0);
983 	*ry = ctx->yoff + py - ctx->woy;
984 
985 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
986 		/* All visible. */
987 		*i = 0;
988 		*x = ctx->xoff + px - ctx->wox;
989 		*rx = nx;
990 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
991 		/* Both left and right not visible. */
992 		*i = ctx->wox;
993 		*x = 0;
994 		*rx = ctx->wsx;
995 	} else if (xoff < ctx->wox) {
996 		/* Left not visible. */
997 		*i = ctx->wox - (ctx->xoff + px);
998 		*x = 0;
999 		*rx = nx - *i;
1000 	} else {
1001 		/* Right not visible. */
1002 		*i = 0;
1003 		*x = (ctx->xoff + px) - ctx->wox;
1004 		*rx = ctx->wsx - *x;
1005 	}
1006 	if (*rx > nx)
1007 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1008 
1009 	return (1);
1010 }
1011 
1012 /* Clear a line. */
1013 static void
1014 tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
1015     u_int px, u_int nx, u_int bg)
1016 {
1017 	struct client	*c = tty->client;
1018 
1019 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1020 
1021 	/* Nothing to clear. */
1022 	if (nx == 0)
1023 		return;
1024 
1025 	/* If genuine BCE is available, can try escape sequences. */
1026 	if (!tty_fake_bce(tty, defaults, bg)) {
1027 		/* Off the end of the line, use EL if available. */
1028 		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
1029 			tty_cursor(tty, px, py);
1030 			tty_putcode(tty, TTYC_EL);
1031 			return;
1032 		}
1033 
1034 		/* At the start of the line. Use EL1. */
1035 		if (px == 0 && tty_term_has(tty->term, TTYC_EL1)) {
1036 			tty_cursor(tty, px + nx - 1, py);
1037 			tty_putcode(tty, TTYC_EL1);
1038 			return;
1039 		}
1040 
1041 		/* Section of line. Use ECH if possible. */
1042 		if (tty_term_has(tty->term, TTYC_ECH)) {
1043 			tty_cursor(tty, px, py);
1044 			tty_putcode1(tty, TTYC_ECH, nx);
1045 			return;
1046 		}
1047 	}
1048 
1049 	/* Couldn't use an escape sequence, use spaces. */
1050 	tty_cursor(tty, px, py);
1051 	tty_repeat_space(tty, nx);
1052 }
1053 
1054 /* Clear a line, adjusting to visible part of pane. */
1055 static void
1056 tty_clear_pane_line(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1057     u_int px, u_int nx, u_int bg)
1058 {
1059 	struct client	*c = tty->client;
1060 	u_int		 i, x, rx, ry;
1061 
1062 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1063 
1064 	if (tty_clamp_line(tty, ctx, px, py, nx, &i, &x, &rx, &ry))
1065 		tty_clear_line(tty, &ctx->defaults, ry, x, rx, bg);
1066 }
1067 
1068 /* Clamp area position to visible part of pane. */
1069 static int
1070 tty_clamp_area(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1071     u_int nx, u_int ny, u_int *i, u_int *j, u_int *x, u_int *y, u_int *rx,
1072     u_int *ry)
1073 {
1074 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1075 
1076 	if (!tty_is_visible(tty, ctx, px, py, nx, ny))
1077 		return (0);
1078 
1079 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1080 		/* All visible. */
1081 		*i = 0;
1082 		*x = ctx->xoff + px - ctx->wox;
1083 		*rx = nx;
1084 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1085 		/* Both left and right not visible. */
1086 		*i = ctx->wox;
1087 		*x = 0;
1088 		*rx = ctx->wsx;
1089 	} else if (xoff < ctx->wox) {
1090 		/* Left not visible. */
1091 		*i = ctx->wox - (ctx->xoff + px);
1092 		*x = 0;
1093 		*rx = nx - *i;
1094 	} else {
1095 		/* Right not visible. */
1096 		*i = 0;
1097 		*x = (ctx->xoff + px) - ctx->wox;
1098 		*rx = ctx->wsx - *x;
1099 	}
1100 	if (*rx > nx)
1101 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1102 
1103 	if (yoff >= ctx->woy && yoff + ny <= ctx->woy + ctx->wsy) {
1104 		/* All visible. */
1105 		*j = 0;
1106 		*y = ctx->yoff + py - ctx->woy;
1107 		*ry = ny;
1108 	} else if (yoff < ctx->woy && yoff + ny > ctx->woy + ctx->wsy) {
1109 		/* Both top and bottom not visible. */
1110 		*j = ctx->woy;
1111 		*y = 0;
1112 		*ry = ctx->wsy;
1113 	} else if (yoff < ctx->woy) {
1114 		/* Top not visible. */
1115 		*j = ctx->woy - (ctx->yoff + py);
1116 		*y = 0;
1117 		*ry = ny - *j;
1118 	} else {
1119 		/* Bottom not visible. */
1120 		*j = 0;
1121 		*y = (ctx->yoff + py) - ctx->woy;
1122 		*ry = ctx->wsy - *y;
1123 	}
1124 	if (*ry > ny)
1125 		fatalx("%s: y too big, %u > %u", __func__, *ry, ny);
1126 
1127 	return (1);
1128 }
1129 
1130 /* Clear an area, adjusting to visible part of pane. */
1131 static void
1132 tty_clear_area(struct tty *tty, const struct grid_cell *defaults, u_int py,
1133     u_int ny, u_int px, u_int nx, u_int bg)
1134 {
1135 	struct client	*c = tty->client;
1136 	u_int		 yy;
1137 	char		 tmp[64];
1138 
1139 	log_debug("%s: %s, %u,%u at %u,%u", __func__, c->name, nx, ny, px, py);
1140 
1141 	/* Nothing to clear. */
1142 	if (nx == 0 || ny == 0)
1143 		return;
1144 
1145 	/* If genuine BCE is available, can try escape sequences. */
1146 	if (!tty_fake_bce(tty, defaults, bg)) {
1147 		/* Use ED if clearing off the bottom of the terminal. */
1148 		if (px == 0 &&
1149 		    px + nx >= tty->sx &&
1150 		    py + ny >= tty->sy &&
1151 		    tty_term_has(tty->term, TTYC_ED)) {
1152 			tty_cursor(tty, 0, py);
1153 			tty_putcode(tty, TTYC_ED);
1154 			return;
1155 		}
1156 
1157 		/*
1158 		 * On VT420 compatible terminals we can use DECFRA if the
1159 		 * background colour isn't default (because it doesn't work
1160 		 * after SGR 0).
1161 		 */
1162 		if ((tty->term->flags & TERM_DECFRA) && !COLOUR_DEFAULT(bg)) {
1163 			xsnprintf(tmp, sizeof tmp, "\033[32;%u;%u;%u;%u$x",
1164 			    py + 1, px + 1, py + ny, px + nx);
1165 			tty_puts(tty, tmp);
1166 			return;
1167 		}
1168 
1169 		/* Full lines can be scrolled away to clear them. */
1170 		if (px == 0 &&
1171 		    px + nx >= tty->sx &&
1172 		    ny > 2 &&
1173 		    tty_term_has(tty->term, TTYC_CSR) &&
1174 		    tty_term_has(tty->term, TTYC_INDN)) {
1175 			tty_region(tty, py, py + ny - 1);
1176 			tty_margin_off(tty);
1177 			tty_putcode1(tty, TTYC_INDN, ny);
1178 			return;
1179 		}
1180 
1181 		/*
1182 		 * If margins are supported, can just scroll the area off to
1183 		 * clear it.
1184 		 */
1185 		if (nx > 2 &&
1186 		    ny > 2 &&
1187 		    tty_term_has(tty->term, TTYC_CSR) &&
1188 		    tty_use_margin(tty) &&
1189 		    tty_term_has(tty->term, TTYC_INDN)) {
1190 			tty_region(tty, py, py + ny - 1);
1191 			tty_margin(tty, px, px + nx - 1);
1192 			tty_putcode1(tty, TTYC_INDN, ny);
1193 			return;
1194 		}
1195 	}
1196 
1197 	/* Couldn't use an escape sequence, loop over the lines. */
1198 	for (yy = py; yy < py + ny; yy++)
1199 		tty_clear_line(tty, defaults, yy, px, nx, bg);
1200 }
1201 
1202 /* Clear an area in a pane. */
1203 static void
1204 tty_clear_pane_area(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1205     u_int ny, u_int px, u_int nx, u_int bg)
1206 {
1207 	u_int	i, j, x, y, rx, ry;
1208 
1209 	if (tty_clamp_area(tty, ctx, px, py, nx, ny, &i, &j, &x, &y, &rx, &ry))
1210 		tty_clear_area(tty, &ctx->defaults, y, ry, x, rx, bg);
1211 }
1212 
1213 static void
1214 tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
1215 {
1216 	struct screen	*s = ctx->s;
1217 	u_int		 nx = ctx->sx, i, x, rx, ry;
1218 
1219 	log_debug("%s: %s %u %d", __func__, tty->client->name, py, ctx->bigger);
1220 
1221 	if (!ctx->bigger) {
1222 		tty_draw_line(tty, s, 0, py, nx, ctx->xoff, ctx->yoff + py,
1223 		    &ctx->defaults, ctx->palette);
1224 		return;
1225 	}
1226 	if (tty_clamp_line(tty, ctx, 0, py, nx, &i, &x, &rx, &ry)) {
1227 		tty_draw_line(tty, s, i, py, rx, x, ry, &ctx->defaults,
1228 		    ctx->palette);
1229 	}
1230 }
1231 
1232 static const struct grid_cell *
1233 tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
1234 {
1235 	static struct grid_cell	new;
1236 	int			c;
1237 
1238 	/* Characters less than 0x7f are always fine, no matter what. */
1239 	if (gc->data.size == 1 && *gc->data.data < 0x7f)
1240 		return (gc);
1241 
1242 	/* UTF-8 terminal and a UTF-8 character - fine. */
1243 	if (tty->client->flags & CLIENT_UTF8)
1244 		return (gc);
1245 	memcpy(&new, gc, sizeof new);
1246 
1247 	/* See if this can be mapped to an ACS character. */
1248 	c = tty_acs_reverse_get(tty, gc->data.data, gc->data.size);
1249 	if (c != -1) {
1250 		utf8_set(&new.data, c);
1251 		new.attr |= GRID_ATTR_CHARSET;
1252 		return (&new);
1253 	}
1254 
1255 	/* Replace by the right number of underscores. */
1256 	new.data.size = gc->data.width;
1257 	if (new.data.size > UTF8_SIZE)
1258 		new.data.size = UTF8_SIZE;
1259 	memset(new.data.data, '_', new.data.size);
1260 	return (&new);
1261 }
1262 
1263 static int
1264 tty_check_overlay(struct tty *tty, u_int px, u_int py)
1265 {
1266 	struct client	*c = tty->client;
1267 
1268 	if (c->overlay_check == NULL)
1269 		return (1);
1270 	return (c->overlay_check(c, px, py));
1271 }
1272 
1273 void
1274 tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
1275     u_int atx, u_int aty, const struct grid_cell *defaults, int *palette)
1276 {
1277 	struct grid		*gd = s->grid;
1278 	struct grid_cell	 gc, last;
1279 	const struct grid_cell	*gcp;
1280 	struct grid_line	*gl;
1281 	u_int			 i, j, ux, sx, width;
1282 	int			 flags, cleared = 0, wrapped = 0;
1283 	char			 buf[512];
1284 	size_t			 len;
1285 	u_int			 cellsize;
1286 
1287 	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__,
1288 	    px, py, nx, atx, aty);
1289 
1290 	/*
1291 	 * py is the line in the screen to draw.
1292 	 * px is the start x and nx is the width to draw.
1293 	 * atx,aty is the line on the terminal to draw it.
1294 	 */
1295 
1296 	flags = (tty->flags & TTY_NOCURSOR);
1297 	tty->flags |= TTY_NOCURSOR;
1298 	tty_update_mode(tty, tty->mode, s);
1299 
1300 	tty_region_off(tty);
1301 	tty_margin_off(tty);
1302 
1303 	/*
1304 	 * Clamp the width to cellsize - note this is not cellused, because
1305 	 * there may be empty background cells after it (from BCE).
1306 	 */
1307 	sx = screen_size_x(s);
1308 	if (nx > sx)
1309 		nx = sx;
1310 	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
1311 	if (sx > cellsize)
1312 		sx = cellsize;
1313 	if (sx > tty->sx)
1314 		sx = tty->sx;
1315 	if (sx > nx)
1316 		sx = nx;
1317 	ux = 0;
1318 
1319 	if (py == 0)
1320 		gl = NULL;
1321 	else
1322 		gl = grid_get_line(gd, gd->hsize + py - 1);
1323 	if (gl == NULL ||
1324 	    (~gl->flags & GRID_LINE_WRAPPED) ||
1325 	    atx != 0 ||
1326 	    tty->cx < tty->sx ||
1327 	    nx < tty->sx) {
1328 		if (nx < tty->sx &&
1329 		    atx == 0 &&
1330 		    px + sx != nx &&
1331 		    tty_term_has(tty->term, TTYC_EL1) &&
1332 		    !tty_fake_bce(tty, defaults, 8)) {
1333 			tty_default_attributes(tty, defaults, palette, 8);
1334 			tty_cursor(tty, nx - 1, aty);
1335 			tty_putcode(tty, TTYC_EL1);
1336 			cleared = 1;
1337 		}
1338 	} else {
1339 		log_debug("%s: wrapped line %u", __func__, aty);
1340 		wrapped = 1;
1341 	}
1342 
1343 	memcpy(&last, &grid_default_cell, sizeof last);
1344 	len = 0;
1345 	width = 0;
1346 
1347 	for (i = 0; i < sx; i++) {
1348 		grid_view_get_cell(gd, px + i, py, &gc);
1349 		gcp = tty_check_codeset(tty, &gc);
1350 		if (len != 0 &&
1351 		    (!tty_check_overlay(tty, atx + ux + width, aty) ||
1352 		    (gcp->attr & GRID_ATTR_CHARSET) ||
1353 		    gcp->flags != last.flags ||
1354 		    gcp->attr != last.attr ||
1355 		    gcp->fg != last.fg ||
1356 		    gcp->bg != last.bg ||
1357 		    gcp->us != last.us ||
1358 		    ux + width + gcp->data.width > nx ||
1359 		    (sizeof buf) - len < gcp->data.size)) {
1360 			tty_attributes(tty, &last, defaults, palette);
1361 			if (last.flags & GRID_FLAG_CLEARED) {
1362 				log_debug("%s: %zu cleared", __func__, len);
1363 				tty_clear_line(tty, defaults, aty, atx + ux,
1364 				    width, last.bg);
1365 			} else {
1366 				if (!wrapped || atx != 0 || ux != 0)
1367 					tty_cursor(tty, atx + ux, aty);
1368 				tty_putn(tty, buf, len, width);
1369 			}
1370 			ux += width;
1371 
1372 			len = 0;
1373 			width = 0;
1374 			wrapped = 0;
1375 		}
1376 
1377 		if (gcp->flags & GRID_FLAG_SELECTED)
1378 			screen_select_cell(s, &last, gcp);
1379 		else
1380 			memcpy(&last, gcp, sizeof last);
1381 		if (!tty_check_overlay(tty, atx + ux, aty)) {
1382 			if (~gcp->flags & GRID_FLAG_PADDING)
1383 				ux += gcp->data.width;
1384 		} else if (ux + gcp->data.width > nx) {
1385 			tty_attributes(tty, &last, defaults, palette);
1386 			tty_cursor(tty, atx + ux, aty);
1387 			for (j = 0; j < gcp->data.width; j++) {
1388 				if (ux + j > nx)
1389 					break;
1390 				tty_putc(tty, ' ');
1391 				ux++;
1392 			}
1393 		} else if (gcp->attr & GRID_ATTR_CHARSET) {
1394 			tty_attributes(tty, &last, defaults, palette);
1395 			tty_cursor(tty, atx + ux, aty);
1396 			for (j = 0; j < gcp->data.size; j++)
1397 				tty_putc(tty, gcp->data.data[j]);
1398 			ux += gcp->data.width;
1399 		} else if (~gcp->flags & GRID_FLAG_PADDING) {
1400 			memcpy(buf + len, gcp->data.data, gcp->data.size);
1401 			len += gcp->data.size;
1402 			width += gcp->data.width;
1403 		}
1404 	}
1405 	if (len != 0 && ((~last.flags & GRID_FLAG_CLEARED) || last.bg != 8)) {
1406 		tty_attributes(tty, &last, defaults, palette);
1407 		if (last.flags & GRID_FLAG_CLEARED) {
1408 			log_debug("%s: %zu cleared (end)", __func__, len);
1409 			tty_clear_line(tty, defaults, aty, atx + ux, width,
1410 			    last.bg);
1411 		} else {
1412 			if (!wrapped || atx != 0 || ux != 0)
1413 				tty_cursor(tty, atx + ux, aty);
1414 			tty_putn(tty, buf, len, width);
1415 		}
1416 		ux += width;
1417 	}
1418 
1419 	if (!cleared && ux < nx) {
1420 		log_debug("%s: %u to end of line (%zu cleared)", __func__,
1421 		    nx - ux, len);
1422 		tty_default_attributes(tty, defaults, palette, 8);
1423 		tty_clear_line(tty, defaults, aty, atx + ux, nx - ux, 8);
1424 	}
1425 
1426 	tty->flags = (tty->flags & ~TTY_NOCURSOR) | flags;
1427 	tty_update_mode(tty, tty->mode, s);
1428 }
1429 
1430 void
1431 tty_sync_start(struct tty *tty)
1432 {
1433 	if (tty->flags & TTY_BLOCK)
1434 		return;
1435 	if (tty->flags & TTY_SYNCING)
1436 		return;
1437 	tty->flags |= TTY_SYNCING;
1438 
1439 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1440 		log_debug("%s sync start", tty->client->name);
1441 		tty_putcode1(tty, TTYC_SYNC, 1);
1442 	}
1443 }
1444 
1445 void
1446 tty_sync_end(struct tty *tty)
1447 {
1448 	if (tty->flags & TTY_BLOCK)
1449 		return;
1450 	if (~tty->flags & TTY_SYNCING)
1451 		return;
1452 	tty->flags &= ~TTY_SYNCING;
1453 
1454 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1455  		log_debug("%s sync end", tty->client->name);
1456 		tty_putcode1(tty, TTYC_SYNC, 2);
1457 	}
1458 }
1459 
1460 static int
1461 tty_client_ready(struct client *c)
1462 {
1463 	if (c->session == NULL || c->tty.term == NULL)
1464 		return (0);
1465 	if (c->flags & (CLIENT_REDRAWWINDOW|CLIENT_SUSPENDED))
1466 		return (0);
1467 	if (c->tty.flags & TTY_FREEZE)
1468 		return (0);
1469 	return (1);
1470 }
1471 
1472 void
1473 tty_write(void (*cmdfn)(struct tty *, const struct tty_ctx *),
1474     struct tty_ctx *ctx)
1475 {
1476 	struct client	*c;
1477 	int		 state;
1478 
1479 	if (ctx->set_client_cb == NULL)
1480 		return;
1481 	TAILQ_FOREACH(c, &clients, entry) {
1482 		if (!tty_client_ready(c))
1483 			continue;
1484 		state = ctx->set_client_cb(ctx, c);
1485 		if (state == -1)
1486 			break;
1487 		if (state == 0)
1488 			continue;
1489 		cmdfn(&c->tty, ctx);
1490 	}
1491 }
1492 
1493 void
1494 tty_cmd_insertcharacter(struct tty *tty, const struct tty_ctx *ctx)
1495 {
1496 	if (ctx->bigger ||
1497 	    !tty_full_width(tty, ctx) ||
1498 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1499 	    (!tty_term_has(tty->term, TTYC_ICH) &&
1500 	    !tty_term_has(tty->term, TTYC_ICH1))) {
1501 		tty_draw_pane(tty, ctx, ctx->ocy);
1502 		return;
1503 	}
1504 
1505 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1506 
1507 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1508 
1509 	tty_emulate_repeat(tty, TTYC_ICH, TTYC_ICH1, ctx->num);
1510 }
1511 
1512 void
1513 tty_cmd_deletecharacter(struct tty *tty, const struct tty_ctx *ctx)
1514 {
1515 	if (ctx->bigger ||
1516 	    !tty_full_width(tty, ctx) ||
1517 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1518 	    (!tty_term_has(tty->term, TTYC_DCH) &&
1519 	    !tty_term_has(tty->term, TTYC_DCH1))) {
1520 		tty_draw_pane(tty, ctx, ctx->ocy);
1521 		return;
1522 	}
1523 
1524 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1525 
1526 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1527 
1528 	tty_emulate_repeat(tty, TTYC_DCH, TTYC_DCH1, ctx->num);
1529 }
1530 
1531 void
1532 tty_cmd_clearcharacter(struct tty *tty, const struct tty_ctx *ctx)
1533 {
1534 	if (ctx->bigger) {
1535 		tty_draw_pane(tty, ctx, ctx->ocy);
1536 		return;
1537 	}
1538 
1539 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1540 
1541 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1542 
1543 	if (tty_term_has(tty->term, TTYC_ECH) &&
1544 	    !tty_fake_bce(tty, &ctx->defaults, 8))
1545 		tty_putcode1(tty, TTYC_ECH, ctx->num);
1546 	else
1547 		tty_repeat_space(tty, ctx->num);
1548 }
1549 
1550 void
1551 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
1552 {
1553 	if (ctx->bigger ||
1554 	    !tty_full_width(tty, ctx) ||
1555 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1556 	    !tty_term_has(tty->term, TTYC_CSR) ||
1557 	    !tty_term_has(tty->term, TTYC_IL1) ||
1558 	    ctx->sx == 1 ||
1559 	    ctx->sy == 1) {
1560 		tty_redraw_region(tty, ctx);
1561 		return;
1562 	}
1563 
1564 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1565 
1566 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1567 	tty_margin_off(tty);
1568 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1569 
1570 	tty_emulate_repeat(tty, TTYC_IL, TTYC_IL1, ctx->num);
1571 	tty->cx = tty->cy = UINT_MAX;
1572 }
1573 
1574 void
1575 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
1576 {
1577 	if (ctx->bigger ||
1578 	    !tty_full_width(tty, ctx) ||
1579 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1580 	    !tty_term_has(tty->term, TTYC_CSR) ||
1581 	    !tty_term_has(tty->term, TTYC_DL1) ||
1582 	    ctx->sx == 1 ||
1583 	    ctx->sy == 1) {
1584 		tty_redraw_region(tty, ctx);
1585 		return;
1586 	}
1587 
1588 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1589 
1590 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1591 	tty_margin_off(tty);
1592 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1593 
1594 	tty_emulate_repeat(tty, TTYC_DL, TTYC_DL1, ctx->num);
1595 	tty->cx = tty->cy = UINT_MAX;
1596 }
1597 
1598 void
1599 tty_cmd_clearline(struct tty *tty, const struct tty_ctx *ctx)
1600 {
1601 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1602 
1603 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->sx, ctx->bg);
1604 }
1605 
1606 void
1607 tty_cmd_clearendofline(struct tty *tty, const struct tty_ctx *ctx)
1608 {
1609 	u_int	nx = ctx->sx - ctx->ocx;
1610 
1611 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1612 
1613 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, nx, ctx->bg);
1614 }
1615 
1616 void
1617 tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
1618 {
1619 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1620 
1621 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->ocx + 1, ctx->bg);
1622 }
1623 
1624 void
1625 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
1626 {
1627 	if (ctx->ocy != ctx->orupper)
1628 		return;
1629 
1630 	if (ctx->bigger ||
1631 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1632 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1633 	    !tty_term_has(tty->term, TTYC_CSR) ||
1634 	    (!tty_term_has(tty->term, TTYC_RI) &&
1635 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1636 	    ctx->sx == 1 ||
1637 	    ctx->sy == 1) {
1638 		tty_redraw_region(tty, ctx);
1639 		return;
1640 	}
1641 
1642 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1643 
1644 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1645 	tty_margin_pane(tty, ctx);
1646 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1647 
1648 	if (tty_term_has(tty->term, TTYC_RI))
1649 		tty_putcode(tty, TTYC_RI);
1650 	else
1651 		tty_putcode1(tty, TTYC_RIN, 1);
1652 }
1653 
1654 void
1655 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
1656 {
1657 	if (ctx->ocy != ctx->orlower)
1658 		return;
1659 
1660 	if (ctx->bigger ||
1661 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1662 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1663 	    !tty_term_has(tty->term, TTYC_CSR) ||
1664 	    ctx->sx == 1 ||
1665 	    ctx->sy == 1) {
1666 		tty_redraw_region(tty, ctx);
1667 		return;
1668 	}
1669 
1670 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1671 
1672 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1673 	tty_margin_pane(tty, ctx);
1674 
1675 	/*
1676 	 * If we want to wrap a pane while using margins, the cursor needs to
1677 	 * be exactly on the right of the region. If the cursor is entirely off
1678 	 * the edge - move it back to the right. Some terminals are funny about
1679 	 * this and insert extra spaces, so only use the right if margins are
1680 	 * enabled.
1681 	 */
1682 	if (ctx->xoff + ctx->ocx > tty->rright) {
1683 		if (!tty_use_margin(tty))
1684 			tty_cursor(tty, 0, ctx->yoff + ctx->ocy);
1685 		else
1686 			tty_cursor(tty, tty->rright, ctx->yoff + ctx->ocy);
1687 	} else
1688 		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1689 
1690 	tty_putc(tty, '\n');
1691 }
1692 
1693 void
1694 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
1695 {
1696 	u_int	i;
1697 
1698 	if (ctx->bigger ||
1699 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1700 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1701 	    !tty_term_has(tty->term, TTYC_CSR) ||
1702 	    ctx->sx == 1 ||
1703 	    ctx->sy == 1) {
1704 		tty_redraw_region(tty, ctx);
1705 		return;
1706 	}
1707 
1708 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1709 
1710 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1711 	tty_margin_pane(tty, ctx);
1712 
1713 	if (ctx->num == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
1714 		if (!tty_use_margin(tty))
1715 			tty_cursor(tty, 0, tty->rlower);
1716 		else
1717 			tty_cursor(tty, tty->rright, tty->rlower);
1718 		for (i = 0; i < ctx->num; i++)
1719 			tty_putc(tty, '\n');
1720 	} else {
1721 		if (tty->cy == UINT_MAX)
1722 			tty_cursor(tty, 0, 0);
1723 		else
1724 			tty_cursor(tty, 0, tty->cy);
1725 		tty_putcode1(tty, TTYC_INDN, ctx->num);
1726 	}
1727 }
1728 
1729 void
1730 tty_cmd_scrolldown(struct tty *tty, const struct tty_ctx *ctx)
1731 {
1732 	u_int	i;
1733 
1734 	if (ctx->bigger ||
1735 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1736 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1737 	    !tty_term_has(tty->term, TTYC_CSR) ||
1738 	    (!tty_term_has(tty->term, TTYC_RI) &&
1739 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1740 	    ctx->sx == 1 ||
1741 	    ctx->sy == 1) {
1742 		tty_redraw_region(tty, ctx);
1743 		return;
1744 	}
1745 
1746 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1747 
1748 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1749 	tty_margin_pane(tty, ctx);
1750 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1751 
1752 	if (tty_term_has(tty->term, TTYC_RIN))
1753 		tty_putcode1(tty, TTYC_RIN, ctx->num);
1754 	else {
1755 		for (i = 0; i < ctx->num; i++)
1756 			tty_putcode(tty, TTYC_RI);
1757 	}
1758 }
1759 
1760 void
1761 tty_cmd_clearendofscreen(struct tty *tty, const struct tty_ctx *ctx)
1762 {
1763 	u_int	px, py, nx, ny;
1764 
1765 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1766 
1767 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1768 	tty_margin_off(tty);
1769 
1770 	px = 0;
1771 	nx = ctx->sx;
1772 	py = ctx->ocy + 1;
1773 	ny = ctx->sy - ctx->ocy - 1;
1774 
1775 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1776 
1777 	px = ctx->ocx;
1778 	nx = ctx->sx - ctx->ocx;
1779 	py = ctx->ocy;
1780 
1781 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1782 }
1783 
1784 void
1785 tty_cmd_clearstartofscreen(struct tty *tty, const struct tty_ctx *ctx)
1786 {
1787 	u_int	px, py, nx, ny;
1788 
1789 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1790 
1791 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1792 	tty_margin_off(tty);
1793 
1794 	px = 0;
1795 	nx = ctx->sx;
1796 	py = 0;
1797 	ny = ctx->ocy;
1798 
1799 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1800 
1801 	px = 0;
1802 	nx = ctx->ocx + 1;
1803 	py = ctx->ocy;
1804 
1805 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1806 }
1807 
1808 void
1809 tty_cmd_clearscreen(struct tty *tty, const struct tty_ctx *ctx)
1810 {
1811 	u_int	px, py, nx, ny;
1812 
1813 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1814 
1815 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1816 	tty_margin_off(tty);
1817 
1818 	px = 0;
1819 	nx = ctx->sx;
1820 	py = 0;
1821 	ny = ctx->sy;
1822 
1823 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1824 }
1825 
1826 void
1827 tty_cmd_alignmenttest(struct tty *tty, const struct tty_ctx *ctx)
1828 {
1829 	u_int	i, j;
1830 
1831 	if (ctx->bigger) {
1832 		ctx->redraw_cb(ctx);
1833 		return;
1834 	}
1835 
1836 	tty_attributes(tty, &grid_default_cell, &ctx->defaults, ctx->palette);
1837 
1838 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1839 	tty_margin_off(tty);
1840 
1841 	for (j = 0; j < ctx->sy; j++) {
1842 		tty_cursor_pane(tty, ctx, 0, j);
1843 		for (i = 0; i < ctx->sx; i++)
1844 			tty_putc(tty, 'E');
1845 	}
1846 }
1847 
1848 void
1849 tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
1850 {
1851 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1))
1852 		return;
1853 
1854 	if (ctx->xoff + ctx->ocx - ctx->wox > tty->sx - 1 &&
1855 	    ctx->ocy == ctx->orlower &&
1856 	    tty_full_width(tty, ctx))
1857 		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1858 
1859 	tty_margin_off(tty);
1860 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
1861 
1862 	tty_cell(tty, ctx->cell, &ctx->defaults, ctx->palette);
1863 }
1864 
1865 void
1866 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
1867 {
1868 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, ctx->num, 1))
1869 		return;
1870 
1871 	if (ctx->bigger &&
1872 	    (ctx->xoff + ctx->ocx < ctx->wox ||
1873 	    ctx->xoff + ctx->ocx + ctx->num > ctx->wox + ctx->wsx)) {
1874 		if (!ctx->wrapped ||
1875 		    !tty_full_width(tty, ctx) ||
1876 		    (tty->term->flags & TERM_NOAM) ||
1877 		    ctx->xoff + ctx->ocx != 0 ||
1878 		    ctx->yoff + ctx->ocy != tty->cy + 1 ||
1879 		    tty->cx < tty->sx ||
1880 		    tty->cy == tty->rlower)
1881 			tty_draw_pane(tty, ctx, ctx->ocy);
1882 		else
1883 			ctx->redraw_cb(ctx);
1884 		return;
1885 	}
1886 
1887 	tty_margin_off(tty);
1888 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
1889 
1890 	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette);
1891 	tty_putn(tty, ctx->ptr, ctx->num, ctx->num);
1892 }
1893 
1894 void
1895 tty_cmd_setselection(struct tty *tty, const struct tty_ctx *ctx)
1896 {
1897 	tty_set_selection(tty, ctx->ptr, ctx->num);
1898 }
1899 
1900 void
1901 tty_set_selection(struct tty *tty, const char *buf, size_t len)
1902 {
1903 	char	*encoded;
1904 	size_t	 size;
1905 
1906 	if (~tty->flags & TTY_STARTED)
1907 		return;
1908 	if (!tty_term_has(tty->term, TTYC_MS))
1909 		return;
1910 
1911 	size = 4 * ((len + 2) / 3) + 1; /* storage for base64 */
1912 	encoded = xmalloc(size);
1913 
1914 	b64_ntop(buf, len, encoded, size);
1915 	tty_putcode_ptr2(tty, TTYC_MS, "", encoded);
1916 
1917 	free(encoded);
1918 }
1919 
1920 void
1921 tty_cmd_rawstring(struct tty *tty, const struct tty_ctx *ctx)
1922 {
1923 	tty_add(tty, ctx->ptr, ctx->num);
1924 	tty_invalidate(tty);
1925 }
1926 
1927 void
1928 tty_cmd_syncstart(struct tty *tty, __unused const struct tty_ctx *ctx)
1929 {
1930 	tty_sync_start(tty);
1931 }
1932 
1933 void
1934 tty_cell(struct tty *tty, const struct grid_cell *gc,
1935     const struct grid_cell *defaults, int *palette)
1936 {
1937 	const struct grid_cell	*gcp;
1938 
1939 	/* Skip last character if terminal is stupid. */
1940 	if ((tty->term->flags & TERM_NOAM) &&
1941 	    tty->cy == tty->sy - 1 &&
1942 	    tty->cx == tty->sx - 1)
1943 		return;
1944 
1945 	/* If this is a padding character, do nothing. */
1946 	if (gc->flags & GRID_FLAG_PADDING)
1947 		return;
1948 
1949 	/* Check the output codeset and apply attributes. */
1950 	gcp = tty_check_codeset(tty, gc);
1951 	tty_attributes(tty, gcp, defaults, palette);
1952 
1953 	/* If it is a single character, write with putc to handle ACS. */
1954 	if (gcp->data.size == 1) {
1955 		tty_attributes(tty, gcp, defaults, palette);
1956 		if (*gcp->data.data < 0x20 || *gcp->data.data == 0x7f)
1957 			return;
1958 		tty_putc(tty, *gcp->data.data);
1959 		return;
1960 	}
1961 
1962 	/* Write the data. */
1963 	tty_putn(tty, gcp->data.data, gcp->data.size, gcp->data.width);
1964 }
1965 
1966 void
1967 tty_reset(struct tty *tty)
1968 {
1969 	struct grid_cell	*gc = &tty->cell;
1970 
1971 	if (!grid_cells_equal(gc, &grid_default_cell)) {
1972 		if ((gc->attr & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
1973 			tty_putcode(tty, TTYC_RMACS);
1974 		tty_putcode(tty, TTYC_SGR0);
1975 		memcpy(gc, &grid_default_cell, sizeof *gc);
1976 	}
1977 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
1978 }
1979 
1980 static void
1981 tty_invalidate(struct tty *tty)
1982 {
1983 	memcpy(&tty->cell, &grid_default_cell, sizeof tty->cell);
1984 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
1985 
1986 	tty->cx = tty->cy = UINT_MAX;
1987 	tty->rupper = tty->rleft = UINT_MAX;
1988 	tty->rlower = tty->rright = UINT_MAX;
1989 
1990 	if (tty->flags & TTY_STARTED) {
1991 		if (tty_use_margin(tty))
1992 			tty_putcode(tty, TTYC_ENMG);
1993 		tty_putcode(tty, TTYC_SGR0);
1994 
1995 		tty->mode = ALL_MODES;
1996 		tty_update_mode(tty, MODE_CURSOR, NULL);
1997 
1998 		tty_cursor(tty, 0, 0);
1999 		tty_region_off(tty);
2000 		tty_margin_off(tty);
2001 	} else
2002 		tty->mode = MODE_CURSOR;
2003 }
2004 
2005 /* Turn off margin. */
2006 void
2007 tty_region_off(struct tty *tty)
2008 {
2009 	tty_region(tty, 0, tty->sy - 1);
2010 }
2011 
2012 /* Set region inside pane. */
2013 static void
2014 tty_region_pane(struct tty *tty, const struct tty_ctx *ctx, u_int rupper,
2015     u_int rlower)
2016 {
2017 	tty_region(tty, ctx->yoff + rupper - ctx->woy,
2018 	    ctx->yoff + rlower - ctx->woy);
2019 }
2020 
2021 /* Set region at absolute position. */
2022 static void
2023 tty_region(struct tty *tty, u_int rupper, u_int rlower)
2024 {
2025 	if (tty->rlower == rlower && tty->rupper == rupper)
2026 		return;
2027 	if (!tty_term_has(tty->term, TTYC_CSR))
2028 		return;
2029 
2030 	tty->rupper = rupper;
2031 	tty->rlower = rlower;
2032 
2033 	/*
2034 	 * Some terminals (such as PuTTY) do not correctly reset the cursor to
2035 	 * 0,0 if it is beyond the last column (they do not reset their wrap
2036 	 * flag so further output causes a line feed). As a workaround, do an
2037 	 * explicit move to 0 first.
2038 	 */
2039 	if (tty->cx >= tty->sx) {
2040 		if (tty->cy == UINT_MAX)
2041 			tty_cursor(tty, 0, 0);
2042 		else
2043 			tty_cursor(tty, 0, tty->cy);
2044 	}
2045 
2046 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2047 	tty->cx = tty->cy = UINT_MAX;
2048 }
2049 
2050 /* Turn off margin. */
2051 void
2052 tty_margin_off(struct tty *tty)
2053 {
2054 	tty_margin(tty, 0, tty->sx - 1);
2055 }
2056 
2057 /* Set margin inside pane. */
2058 static void
2059 tty_margin_pane(struct tty *tty, const struct tty_ctx *ctx)
2060 {
2061 	tty_margin(tty, ctx->xoff - ctx->wox,
2062 	    ctx->xoff + ctx->sx - 1 - ctx->wox);
2063 }
2064 
2065 /* Set margin at absolute position. */
2066 static void
2067 tty_margin(struct tty *tty, u_int rleft, u_int rright)
2068 {
2069 	if (!tty_use_margin(tty))
2070 		return;
2071 	if (tty->rleft == rleft && tty->rright == rright)
2072 		return;
2073 
2074 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2075 
2076 	tty->rleft = rleft;
2077 	tty->rright = rright;
2078 
2079 	if (rleft == 0 && rright == tty->sx - 1)
2080 		tty_putcode(tty, TTYC_CLMG);
2081 	else
2082 		tty_putcode2(tty, TTYC_CMG, rleft, rright);
2083 	tty->cx = tty->cy = UINT_MAX;
2084 }
2085 
2086 /*
2087  * Move the cursor, unless it would wrap itself when the next character is
2088  * printed.
2089  */
2090 static void
2091 tty_cursor_pane_unless_wrap(struct tty *tty, const struct tty_ctx *ctx,
2092     u_int cx, u_int cy)
2093 {
2094 	if (!ctx->wrapped ||
2095 	    !tty_full_width(tty, ctx) ||
2096 	    (tty->term->flags & TERM_NOAM) ||
2097 	    ctx->xoff + cx != 0 ||
2098 	    ctx->yoff + cy != tty->cy + 1 ||
2099 	    tty->cx < tty->sx ||
2100 	    tty->cy == tty->rlower)
2101 		tty_cursor_pane(tty, ctx, cx, cy);
2102 	else
2103 		log_debug("%s: will wrap at %u,%u", __func__, tty->cx, tty->cy);
2104 }
2105 
2106 /* Move cursor inside pane. */
2107 static void
2108 tty_cursor_pane(struct tty *tty, const struct tty_ctx *ctx, u_int cx, u_int cy)
2109 {
2110 	tty_cursor(tty, ctx->xoff + cx - ctx->wox, ctx->yoff + cy - ctx->woy);
2111 }
2112 
2113 /* Move cursor to absolute position. */
2114 void
2115 tty_cursor(struct tty *tty, u_int cx, u_int cy)
2116 {
2117 	struct tty_term	*term = tty->term;
2118 	u_int		 thisx, thisy;
2119 	int		 change;
2120 
2121 	if (tty->flags & TTY_BLOCK)
2122 		return;
2123 
2124 	if (cx > tty->sx - 1)
2125 		cx = tty->sx - 1;
2126 
2127 	thisx = tty->cx;
2128 	thisy = tty->cy;
2129 
2130 	/* No change. */
2131 	if (cx == thisx && cy == thisy)
2132 		return;
2133 
2134 	/* Very end of the line, just use absolute movement. */
2135 	if (thisx > tty->sx - 1)
2136 		goto absolute;
2137 
2138 	/* Move to home position (0, 0). */
2139 	if (cx == 0 && cy == 0 && tty_term_has(term, TTYC_HOME)) {
2140 		tty_putcode(tty, TTYC_HOME);
2141 		goto out;
2142 	}
2143 
2144 	/* Zero on the next line. */
2145 	if (cx == 0 && cy == thisy + 1 && thisy != tty->rlower &&
2146 	    (!tty_use_margin(tty) || tty->rleft == 0)) {
2147 		tty_putc(tty, '\r');
2148 		tty_putc(tty, '\n');
2149 		goto out;
2150 	}
2151 
2152 	/* Moving column or row. */
2153 	if (cy == thisy) {
2154 		/*
2155 		 * Moving column only, row staying the same.
2156 		 */
2157 
2158 		/* To left edge. */
2159 		if (cx == 0 && (!tty_use_margin(tty) || tty->rleft == 0)) {
2160 			tty_putc(tty, '\r');
2161 			goto out;
2162 		}
2163 
2164 		/* One to the left. */
2165 		if (cx == thisx - 1 && tty_term_has(term, TTYC_CUB1)) {
2166 			tty_putcode(tty, TTYC_CUB1);
2167 			goto out;
2168 		}
2169 
2170 		/* One to the right. */
2171 		if (cx == thisx + 1 && tty_term_has(term, TTYC_CUF1)) {
2172 			tty_putcode(tty, TTYC_CUF1);
2173 			goto out;
2174 		}
2175 
2176 		/* Calculate difference. */
2177 		change = thisx - cx;	/* +ve left, -ve right */
2178 
2179 		/*
2180 		 * Use HPA if change is larger than absolute, otherwise move
2181 		 * the cursor with CUB/CUF.
2182 		 */
2183 		if ((u_int) abs(change) > cx && tty_term_has(term, TTYC_HPA)) {
2184 			tty_putcode1(tty, TTYC_HPA, cx);
2185 			goto out;
2186 		} else if (change > 0 &&
2187 		    tty_term_has(term, TTYC_CUB) &&
2188 		    !tty_use_margin(tty)) {
2189 			if (change == 2 && tty_term_has(term, TTYC_CUB1)) {
2190 				tty_putcode(tty, TTYC_CUB1);
2191 				tty_putcode(tty, TTYC_CUB1);
2192 				goto out;
2193 			}
2194 			tty_putcode1(tty, TTYC_CUB, change);
2195 			goto out;
2196 		} else if (change < 0 &&
2197 		    tty_term_has(term, TTYC_CUF) &&
2198 		    !tty_use_margin(tty)) {
2199 			tty_putcode1(tty, TTYC_CUF, -change);
2200 			goto out;
2201 		}
2202 	} else if (cx == thisx) {
2203 		/*
2204 		 * Moving row only, column staying the same.
2205 		 */
2206 
2207 		/* One above. */
2208 		if (thisy != tty->rupper &&
2209 		    cy == thisy - 1 && tty_term_has(term, TTYC_CUU1)) {
2210 			tty_putcode(tty, TTYC_CUU1);
2211 			goto out;
2212 		}
2213 
2214 		/* One below. */
2215 		if (thisy != tty->rlower &&
2216 		    cy == thisy + 1 && tty_term_has(term, TTYC_CUD1)) {
2217 			tty_putcode(tty, TTYC_CUD1);
2218 			goto out;
2219 		}
2220 
2221 		/* Calculate difference. */
2222 		change = thisy - cy;	/* +ve up, -ve down */
2223 
2224 		/*
2225 		 * Try to use VPA if change is larger than absolute or if this
2226 		 * change would cross the scroll region, otherwise use CUU/CUD.
2227 		 */
2228 		if ((u_int) abs(change) > cy ||
2229 		    (change < 0 && cy - change > tty->rlower) ||
2230 		    (change > 0 && cy - change < tty->rupper)) {
2231 			    if (tty_term_has(term, TTYC_VPA)) {
2232 				    tty_putcode1(tty, TTYC_VPA, cy);
2233 				    goto out;
2234 			    }
2235 		} else if (change > 0 && tty_term_has(term, TTYC_CUU)) {
2236 			tty_putcode1(tty, TTYC_CUU, change);
2237 			goto out;
2238 		} else if (change < 0 && tty_term_has(term, TTYC_CUD)) {
2239 			tty_putcode1(tty, TTYC_CUD, -change);
2240 			goto out;
2241 		}
2242 	}
2243 
2244 absolute:
2245 	/* Absolute movement. */
2246 	tty_putcode2(tty, TTYC_CUP, cy, cx);
2247 
2248 out:
2249 	tty->cx = cx;
2250 	tty->cy = cy;
2251 }
2252 
2253 void
2254 tty_attributes(struct tty *tty, const struct grid_cell *gc,
2255     const struct grid_cell *defaults, int *palette)
2256 {
2257 	struct grid_cell	*tc = &tty->cell, gc2;
2258 	int			 changed;
2259 
2260 	/* Copy cell and update default colours. */
2261 	memcpy(&gc2, gc, sizeof gc2);
2262 	if (gc2.fg == 8)
2263 		gc2.fg = defaults->fg;
2264 	if (gc2.bg == 8)
2265 		gc2.bg = defaults->bg;
2266 
2267 	/* Ignore cell if it is the same as the last one. */
2268 	if (gc2.attr == tty->last_cell.attr &&
2269 	    gc2.fg == tty->last_cell.fg &&
2270 	    gc2.bg == tty->last_cell.bg &&
2271 	    gc2.us == tty->last_cell.us)
2272 		return;
2273 
2274 	/*
2275 	 * If no setab, try to use the reverse attribute as a best-effort for a
2276 	 * non-default background. This is a bit of a hack but it doesn't do
2277 	 * any serious harm and makes a couple of applications happier.
2278 	 */
2279 	if (!tty_term_has(tty->term, TTYC_SETAB)) {
2280 		if (gc2.attr & GRID_ATTR_REVERSE) {
2281 			if (gc2.fg != 7 && !COLOUR_DEFAULT(gc2.fg))
2282 				gc2.attr &= ~GRID_ATTR_REVERSE;
2283 		} else {
2284 			if (gc2.bg != 0 && !COLOUR_DEFAULT(gc2.bg))
2285 				gc2.attr |= GRID_ATTR_REVERSE;
2286 		}
2287 	}
2288 
2289 	/* Fix up the colours if necessary. */
2290 	tty_check_fg(tty, palette, &gc2);
2291 	tty_check_bg(tty, palette, &gc2);
2292 	tty_check_us(tty, palette, &gc2);
2293 
2294 	/*
2295 	 * If any bits are being cleared or the underline colour is now default,
2296 	 * reset everything.
2297 	 */
2298 	if ((tc->attr & ~gc2.attr) || (tc->us != gc2.us && gc2.us == 0))
2299 		tty_reset(tty);
2300 
2301 	/*
2302 	 * Set the colours. This may call tty_reset() (so it comes next) and
2303 	 * may add to (NOT remove) the desired attributes.
2304 	 */
2305 	tty_colours(tty, &gc2);
2306 
2307 	/* Filter out attribute bits already set. */
2308 	changed = gc2.attr & ~tc->attr;
2309 	tc->attr = gc2.attr;
2310 
2311 	/* Set the attributes. */
2312 	if (changed & GRID_ATTR_BRIGHT)
2313 		tty_putcode(tty, TTYC_BOLD);
2314 	if (changed & GRID_ATTR_DIM)
2315 		tty_putcode(tty, TTYC_DIM);
2316 	if (changed & GRID_ATTR_ITALICS)
2317 		tty_set_italics(tty);
2318 	if (changed & GRID_ATTR_ALL_UNDERSCORE) {
2319 		if ((changed & GRID_ATTR_UNDERSCORE) ||
2320 		    !tty_term_has(tty->term, TTYC_SMULX))
2321 			tty_putcode(tty, TTYC_SMUL);
2322 		else if (changed & GRID_ATTR_UNDERSCORE_2)
2323 			tty_putcode1(tty, TTYC_SMULX, 2);
2324 		else if (changed & GRID_ATTR_UNDERSCORE_3)
2325 			tty_putcode1(tty, TTYC_SMULX, 3);
2326 		else if (changed & GRID_ATTR_UNDERSCORE_4)
2327 			tty_putcode1(tty, TTYC_SMULX, 4);
2328 		else if (changed & GRID_ATTR_UNDERSCORE_5)
2329 			tty_putcode1(tty, TTYC_SMULX, 5);
2330 	}
2331 	if (changed & GRID_ATTR_BLINK)
2332 		tty_putcode(tty, TTYC_BLINK);
2333 	if (changed & GRID_ATTR_REVERSE) {
2334 		if (tty_term_has(tty->term, TTYC_REV))
2335 			tty_putcode(tty, TTYC_REV);
2336 		else if (tty_term_has(tty->term, TTYC_SMSO))
2337 			tty_putcode(tty, TTYC_SMSO);
2338 	}
2339 	if (changed & GRID_ATTR_HIDDEN)
2340 		tty_putcode(tty, TTYC_INVIS);
2341 	if (changed & GRID_ATTR_STRIKETHROUGH)
2342 		tty_putcode(tty, TTYC_SMXX);
2343 	if (changed & GRID_ATTR_OVERLINE)
2344 		tty_putcode(tty, TTYC_SMOL);
2345 	if ((changed & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2346 		tty_putcode(tty, TTYC_SMACS);
2347 
2348 	memcpy(&tty->last_cell, &gc2, sizeof tty->last_cell);
2349 }
2350 
2351 static void
2352 tty_colours(struct tty *tty, const struct grid_cell *gc)
2353 {
2354 	struct grid_cell	*tc = &tty->cell;
2355 	int			 have_ax;
2356 
2357 	/* No changes? Nothing is necessary. */
2358 	if (gc->fg == tc->fg && gc->bg == tc->bg && gc->us == tc->us)
2359 		return;
2360 
2361 	/*
2362 	 * Is either the default colour? This is handled specially because the
2363 	 * best solution might be to reset both colours to default, in which
2364 	 * case if only one is default need to fall onward to set the other
2365 	 * colour.
2366 	 */
2367 	if (COLOUR_DEFAULT(gc->fg) || COLOUR_DEFAULT(gc->bg)) {
2368 		/*
2369 		 * If don't have AX but do have op, send sgr0 (op can't
2370 		 * actually be used because it is sometimes the same as sgr0
2371 		 * and sometimes isn't). This resets both colours to default.
2372 		 *
2373 		 * Otherwise, try to set the default colour only as needed.
2374 		 */
2375 		have_ax = tty_term_flag(tty->term, TTYC_AX);
2376 		if (!have_ax && tty_term_has(tty->term, TTYC_OP))
2377 			tty_reset(tty);
2378 		else {
2379 			if (COLOUR_DEFAULT(gc->fg) && !COLOUR_DEFAULT(tc->fg)) {
2380 				if (have_ax)
2381 					tty_puts(tty, "\033[39m");
2382 				else if (tc->fg != 7)
2383 					tty_putcode1(tty, TTYC_SETAF, 7);
2384 				tc->fg = gc->fg;
2385 			}
2386 			if (COLOUR_DEFAULT(gc->bg) && !COLOUR_DEFAULT(tc->bg)) {
2387 				if (have_ax)
2388 					tty_puts(tty, "\033[49m");
2389 				else if (tc->bg != 0)
2390 					tty_putcode1(tty, TTYC_SETAB, 0);
2391 				tc->bg = gc->bg;
2392 			}
2393 		}
2394 	}
2395 
2396 	/* Set the foreground colour. */
2397 	if (!COLOUR_DEFAULT(gc->fg) && gc->fg != tc->fg)
2398 		tty_colours_fg(tty, gc);
2399 
2400 	/*
2401 	 * Set the background colour. This must come after the foreground as
2402 	 * tty_colour_fg() can call tty_reset().
2403 	 */
2404 	if (!COLOUR_DEFAULT(gc->bg) && gc->bg != tc->bg)
2405 		tty_colours_bg(tty, gc);
2406 
2407 	/* Set the underscore color. */
2408 	if (gc->us != tc->us)
2409 		tty_colours_us(tty, gc);
2410 }
2411 
2412 static void
2413 tty_check_fg(struct tty *tty, int *palette, struct grid_cell *gc)
2414 {
2415 	u_char	r, g, b;
2416 	u_int	colours;
2417 	int	c;
2418 
2419 	/*
2420 	 * Perform substitution if this pane has a palette. If the bright
2421 	 * attribute is set, use the bright entry in the palette by changing to
2422 	 * the aixterm colour.
2423 	 */
2424 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2425 		c = gc->fg;
2426 		if (c < 8 && gc->attr & GRID_ATTR_BRIGHT)
2427 			c += 90;
2428 		if ((c = tty_get_palette(palette, c)) != -1)
2429 			gc->fg = c;
2430 	}
2431 
2432 	/* Is this a 24-bit colour? */
2433 	if (gc->fg & COLOUR_FLAG_RGB) {
2434 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2435 		if (tty->term->flags & TERM_RGBCOLOURS)
2436 			return;
2437 		colour_split_rgb(gc->fg, &r, &g, &b);
2438 		gc->fg = colour_find_rgb(r, g, b);
2439 	}
2440 
2441 	/* How many colours does this terminal have? */
2442 	if (tty->term->flags & TERM_256COLOURS)
2443 		colours = 256;
2444 	else
2445 		colours = tty_term_number(tty->term, TTYC_COLORS);
2446 
2447 	/* Is this a 256-colour colour? */
2448 	if (gc->fg & COLOUR_FLAG_256) {
2449 		/* And not a 256 colour mode? */
2450 		if (colours < 256) {
2451 			gc->fg = colour_256to16(gc->fg);
2452 			if (gc->fg & 8) {
2453 				gc->fg &= 7;
2454 				if (colours >= 16)
2455 					gc->fg += 90;
2456 			}
2457 		}
2458 		return;
2459 	}
2460 
2461 	/* Is this an aixterm colour? */
2462 	if (gc->fg >= 90 && gc->fg <= 97 && colours < 16) {
2463 		gc->fg -= 90;
2464 		gc->attr |= GRID_ATTR_BRIGHT;
2465 	}
2466 }
2467 
2468 static void
2469 tty_check_bg(struct tty *tty, int *palette, struct grid_cell *gc)
2470 {
2471 	u_char	r, g, b;
2472 	u_int	colours;
2473 	int	c;
2474 
2475 	/* Perform substitution if this pane has a palette. */
2476 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2477 		if ((c = tty_get_palette(palette, gc->bg)) != -1)
2478 			gc->bg = c;
2479 	}
2480 
2481 	/* Is this a 24-bit colour? */
2482 	if (gc->bg & COLOUR_FLAG_RGB) {
2483 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2484 		if (tty->term->flags & TERM_RGBCOLOURS)
2485 			return;
2486 		colour_split_rgb(gc->bg, &r, &g, &b);
2487 		gc->bg = colour_find_rgb(r, g, b);
2488 	}
2489 
2490 	/* How many colours does this terminal have? */
2491 	if (tty->term->flags & TERM_256COLOURS)
2492 		colours = 256;
2493 	else
2494 		colours = tty_term_number(tty->term, TTYC_COLORS);
2495 
2496 	/* Is this a 256-colour colour? */
2497 	if (gc->bg & COLOUR_FLAG_256) {
2498 		/*
2499 		 * And not a 256 colour mode? Translate to 16-colour
2500 		 * palette. Bold background doesn't exist portably, so just
2501 		 * discard the bold bit if set.
2502 		 */
2503 		if (colours < 256) {
2504 			gc->bg = colour_256to16(gc->bg);
2505 			if (gc->bg & 8) {
2506 				gc->bg &= 7;
2507 				if (colours >= 16)
2508 					gc->bg += 90;
2509 			}
2510 		}
2511 		return;
2512 	}
2513 
2514 	/* Is this an aixterm colour? */
2515 	if (gc->bg >= 90 && gc->bg <= 97 && colours < 16)
2516 		gc->bg -= 90;
2517 }
2518 
2519 static void
2520 tty_check_us(__unused struct tty *tty, int *palette, struct grid_cell *gc)
2521 {
2522 	int	c;
2523 
2524 	/* Perform substitution if this pane has a palette. */
2525 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2526 		if ((c = tty_get_palette(palette, gc->us)) != -1)
2527 			gc->us = c;
2528 	}
2529 
2530 	/* Underscore colour is set as RGB so convert a 256 colour to RGB. */
2531 	if (gc->us & COLOUR_FLAG_256)
2532 		gc->us = colour_256toRGB (gc->us);
2533 }
2534 
2535 static void
2536 tty_colours_fg(struct tty *tty, const struct grid_cell *gc)
2537 {
2538 	struct grid_cell	*tc = &tty->cell;
2539 	char			 s[32];
2540 
2541 	/* Is this a 24-bit or 256-colour colour? */
2542 	if (gc->fg & COLOUR_FLAG_RGB || gc->fg & COLOUR_FLAG_256) {
2543 		if (tty_try_colour(tty, gc->fg, "38") == 0)
2544 			goto save;
2545 		/* Should not get here, already converted in tty_check_fg. */
2546 		return;
2547 	}
2548 
2549 	/* Is this an aixterm bright colour? */
2550 	if (gc->fg >= 90 && gc->fg <= 97) {
2551 		if (tty->term->flags & TERM_256COLOURS) {
2552 			xsnprintf(s, sizeof s, "\033[%dm", gc->fg);
2553 			tty_puts(tty, s);
2554 		} else
2555 			tty_putcode1(tty, TTYC_SETAF, gc->fg - 90 + 8);
2556 		goto save;
2557 	}
2558 
2559 	/* Otherwise set the foreground colour. */
2560 	tty_putcode1(tty, TTYC_SETAF, gc->fg);
2561 
2562 save:
2563 	/* Save the new values in the terminal current cell. */
2564 	tc->fg = gc->fg;
2565 }
2566 
2567 static void
2568 tty_colours_bg(struct tty *tty, const struct grid_cell *gc)
2569 {
2570 	struct grid_cell	*tc = &tty->cell;
2571 	char			 s[32];
2572 
2573 	/* Is this a 24-bit or 256-colour colour? */
2574 	if (gc->bg & COLOUR_FLAG_RGB || gc->bg & COLOUR_FLAG_256) {
2575 		if (tty_try_colour(tty, gc->bg, "48") == 0)
2576 			goto save;
2577 		/* Should not get here, already converted in tty_check_bg. */
2578 		return;
2579 	}
2580 
2581 	/* Is this an aixterm bright colour? */
2582 	if (gc->bg >= 90 && gc->bg <= 97) {
2583 		if (tty->term->flags & TERM_256COLOURS) {
2584 			xsnprintf(s, sizeof s, "\033[%dm", gc->bg + 10);
2585 			tty_puts(tty, s);
2586 		} else
2587 			tty_putcode1(tty, TTYC_SETAB, gc->bg - 90 + 8);
2588 		goto save;
2589 	}
2590 
2591 	/* Otherwise set the background colour. */
2592 	tty_putcode1(tty, TTYC_SETAB, gc->bg);
2593 
2594 save:
2595 	/* Save the new values in the terminal current cell. */
2596 	tc->bg = gc->bg;
2597 }
2598 
2599 static void
2600 tty_colours_us(struct tty *tty, const struct grid_cell *gc)
2601 {
2602 	struct grid_cell	*tc = &tty->cell;
2603 	u_int			 c;
2604 	u_char			 r, g, b;
2605 
2606 	/* Clear underline colour. */
2607 	if (gc->us == 0) {
2608 		tty_putcode(tty, TTYC_OL);
2609 		goto save;
2610 	}
2611 
2612 	/* Must be an RGB colour - this should never happen. */
2613 	if (~gc->us & COLOUR_FLAG_RGB)
2614 		return;
2615 
2616 	/*
2617 	 * Setulc and setal follows the ncurses(3) one argument "direct colour"
2618 	 * capability format. Calculate the colour value.
2619 	 */
2620 	colour_split_rgb(gc->us, &r, &g, &b);
2621 	c = (65536 * r) + (256 * g) + b;
2622 
2623 	/*
2624 	 * Write the colour. Only use setal if the RGB flag is set because the
2625 	 * non-RGB version may be wrong.
2626 	 */
2627 	if (tty_term_has(tty->term, TTYC_SETULC))
2628 		tty_putcode1(tty, TTYC_SETULC, c);
2629 	else if (tty_term_has(tty->term, TTYC_SETAL) &&
2630 	    tty_term_has(tty->term, TTYC_RGB))
2631 		tty_putcode1(tty, TTYC_SETAL, c);
2632 
2633 save:
2634 	/* Save the new values in the terminal current cell. */
2635 	tc->us = gc->us;
2636 }
2637 
2638 static int
2639 tty_try_colour(struct tty *tty, int colour, const char *type)
2640 {
2641 	u_char	r, g, b;
2642 
2643 	if (colour & COLOUR_FLAG_256) {
2644 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETAF))
2645 			tty_putcode1(tty, TTYC_SETAF, colour & 0xff);
2646 		else if (tty_term_has(tty->term, TTYC_SETAB))
2647 			tty_putcode1(tty, TTYC_SETAB, colour & 0xff);
2648 		return (0);
2649 	}
2650 
2651 	if (colour & COLOUR_FLAG_RGB) {
2652 		colour_split_rgb(colour & 0xffffff, &r, &g, &b);
2653 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETRGBF))
2654 			tty_putcode3(tty, TTYC_SETRGBF, r, g, b);
2655 		else if (tty_term_has(tty->term, TTYC_SETRGBB))
2656 			tty_putcode3(tty, TTYC_SETRGBB, r, g, b);
2657 		return (0);
2658 	}
2659 
2660 	return (-1);
2661 }
2662 
2663 static void
2664 tty_window_default_style(struct grid_cell *gc, struct window_pane *wp)
2665 {
2666 	memcpy(gc, &grid_default_cell, sizeof *gc);
2667 	gc->fg = wp->fg;
2668 	gc->bg = wp->bg;
2669 }
2670 
2671 void
2672 tty_default_colours(struct grid_cell *gc, struct window_pane *wp)
2673 {
2674 	struct options	*oo = wp->options;
2675 
2676 	memcpy(gc, &grid_default_cell, sizeof *gc);
2677 
2678 	if (wp->flags & PANE_STYLECHANGED) {
2679 		wp->flags &= ~PANE_STYLECHANGED;
2680 
2681 		tty_window_default_style(&wp->cached_active_gc, wp);
2682 		style_add(&wp->cached_active_gc, oo, "window-active-style",
2683 		    NULL);
2684 		tty_window_default_style(&wp->cached_gc, wp);
2685 		style_add(&wp->cached_gc, oo, "window-style", NULL);
2686 	}
2687 
2688 	if (gc->fg == 8) {
2689 		if (wp == wp->window->active && wp->cached_active_gc.fg != 8)
2690 			gc->fg = wp->cached_active_gc.fg;
2691 		else
2692 			gc->fg = wp->cached_gc.fg;
2693 	}
2694 
2695 	if (gc->bg == 8) {
2696 		if (wp == wp->window->active && wp->cached_active_gc.bg != 8)
2697 			gc->bg = wp->cached_active_gc.bg;
2698 		else
2699 			gc->bg = wp->cached_gc.bg;
2700 	}
2701 }
2702 
2703 static void
2704 tty_default_attributes(struct tty *tty, const struct grid_cell *defaults,
2705     int *palette, u_int bg)
2706 {
2707 	struct grid_cell	gc;
2708 
2709 	memcpy(&gc, &grid_default_cell, sizeof gc);
2710 	gc.bg = bg;
2711 	tty_attributes(tty, &gc, defaults, palette);
2712 }
2713